Asthma and Diving: What to Expect at Your Diving Medical. If you have asthma and want to scuba dive, you may be asked to have a medical assessment before you are cleared to dive. This can understandably sound a little daunting, particularly if you have had asthma since childhood, rarely use your inhaler, or feel that your asthma is very well controlled. So, what is the doctor actually looking for — and what can you expect when you attend an asthma diving assessment?